Pyrexia due to pyogenic sacroiliitis with iliopsoas abscess after spinal cord injury.

STUDY DESIGN: Single case report. OBJECTIVES: To present an unusual cause of fever in a patient with spinal cord injury (SCI). SETTING: University Hospital, Belgium. METHODS: A 52-year-old man with a complete T9 paraplegia was admitted to hospital with a 7 day history of fever above 39 degrees C without pain and without gastrointestinal, urinary, or respiratory complaints. The patient had had a flap coverage for a sacral pressure ulcer 6 months prior to admission. RESULTS: Bone scintigraphy demonstrated markedly increased activity in the left sacroiliac joint. Computed tomography (CT) revealed an infection of the left sacroiliac joint with a large abscess involving the iliopsoas muscle. The responsible organism, Pseudomonas aeruginosa, was isolated from abscess liquid obtained by CT-guided aspiration. We postulated that P. aeruginosa had colonized the eschar and, due to the proximity, infected the sacroiliac joint and the adjacent iliopsoas muscle. Prompt intravenous antibiotic therapy ensured clinical improvement and radiological regression. CONCLUSION: Pyogenic sacroiliitis is a relatively rare condition that may be difficult to diagnose in patients with normal sensation, and even more so in SCI patients. As far as we know, psoas abscess associated with pyogenic sacroiliitis has never been described in SCI patients. This infectious pathology must be kept in mind in SCI patients with fever of unknown origin and with a history of sacral eschar.